iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
7cb9994754
linux/fs/ceph/mdsmap.c
Luís Henriques d93231a6bc ceph: prevent a client from exceeding the MDS maximum xattr size 
The MDS tries to enforce a limit on the total key/values in extended
attributes.  However, this limit is enforced only if doing a synchronous
operation (MDS_OP_SETXATTR) -- if we're buffering the xattrs, the MDS
doesn't have a chance to enforce these limits.

This patch adds support for decoding the xattrs maximum size setting that is
distributed in the mdsmap.  Then, when setting an xattr, the kernel client
will revert to do a synchronous operation if that maximum size is exceeded.

While there, fix a dout() that would trigger a printk warning:

[   98.718078] ------------[ cut here ]------------
[   98.719012] precision 65536 too large
[   98.719039] WARNING: CPU: 1 PID: 3755 at lib/vsprintf.c:2703 vsnprintf+0x5e3/0x600
...

Link: https://tracker.ceph.com/issues/55725
Signed-off-by: Luís Henriques <lhenriques@suse.de>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2022-08-03 00:54:12 +02:00

437 lines
11 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
#include <linux/ceph/ceph_debug.h>
#include <linux/bug.h>
#include <linux/err.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/ceph/mdsmap.h>
#include <linux/ceph/messenger.h>
#include <linux/ceph/decode.h>
#include "super.h"
#define CEPH_MDS_IS_READY(i, ignore_laggy) \
(m->m_info[i].state > 0 && ignore_laggy ? true : !m->m_info[i].laggy)
static int __mdsmap_get_random_mds(struct ceph_mdsmap *m, bool ignore_laggy)
{
int n = 0;
int i, j;
/* count */
for (i = 0; i < m->possible_max_rank; i++)
if (CEPH_MDS_IS_READY(i, ignore_laggy))
n++;
if (n == 0)
return -1;
/* pick */
n = prandom_u32() % n;
for (j = 0, i = 0; i < m->possible_max_rank; i++) {
if (CEPH_MDS_IS_READY(i, ignore_laggy))
j++;
if (j > n)
break;
}
return i;
}
/*
* choose a random mds that is "up" (i.e. has a state > 0), or -1.
*/
int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m)
{
int mds;
mds = __mdsmap_get_random_mds(m, false);
if (mds == m->possible_max_rank || mds == -1)
mds = __mdsmap_get_random_mds(m, true);
return mds == m->possible_max_rank ? -1 : mds;
}
#define __decode_and_drop_type(p, end, type, bad) \
do { \
if (*p + sizeof(type) > end) \
goto bad; \
*p += sizeof(type); \
} while (0)
#define __decode_and_drop_set(p, end, type, bad) \
do { \
u32 n; \
size_t need; \
ceph_decode_32_safe(p, end, n, bad); \
need = sizeof(type) * n; \
ceph_decode_need(p, end, need, bad); \
*p += need; \
} while (0)
#define __decode_and_drop_map(p, end, ktype, vtype, bad) \
do { \
u32 n; \
size_t need; \
ceph_decode_32_safe(p, end, n, bad); \
need = (sizeof(ktype) + sizeof(vtype)) * n; \
ceph_decode_need(p, end, need, bad); \
*p += need; \
} while (0)
static int __decode_and_drop_compat_set(void **p, void* end)
{
int i;
/* compat, ro_compat, incompat*/
for (i = 0; i < 3; i++) {
u32 n;
ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad);
/* mask */
*p += sizeof(u64);
/* names (map<u64, string>) */
n = ceph_decode_32(p);
while (n-- > 0) {
u32 len;
ceph_decode_need(p, end, sizeof(u64) + sizeof(u32),
bad);
*p += sizeof(u64);
len = ceph_decode_32(p);
ceph_decode_need(p, end, len, bad);
*p += len;
}
}
return 0;
bad:
return -1;
}
/*
* Decode an MDS map
*
* Ignore any fields we don't care about (there are quite a few of
* them).
*/
struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end, bool msgr2)
{
struct ceph_mdsmap *m;
const void *start = *p;
int i, j, n;
int err;
u8 mdsmap_v;
u16 mdsmap_ev;
u32 target;
m = kzalloc(sizeof(*m), GFP_NOFS);
if (!m)
return ERR_PTR(-ENOMEM);
ceph_decode_need(p, end, 1 + 1, bad);
mdsmap_v = ceph_decode_8(p);
*p += sizeof(u8); /* mdsmap_cv */
if (mdsmap_v >= 4) {
u32 mdsmap_len;
ceph_decode_32_safe(p, end, mdsmap_len, bad);
if (end < *p + mdsmap_len)
goto bad;
end = *p + mdsmap_len;
}
ceph_decode_need(p, end, 8*sizeof(u32) + sizeof(u64), bad);
m->m_epoch = ceph_decode_32(p);
m->m_client_epoch = ceph_decode_32(p);
m->m_last_failure = ceph_decode_32(p);
m->m_root = ceph_decode_32(p);
m->m_session_timeout = ceph_decode_32(p);
m->m_session_autoclose = ceph_decode_32(p);
m->m_max_file_size = ceph_decode_64(p);
m->m_max_mds = ceph_decode_32(p);
/*
* pick out the active nodes as the m_num_active_mds, the
* m_num_active_mds maybe larger than m_max_mds when decreasing
* the max_mds in cluster side, in other case it should less
* than or equal to m_max_mds.
*/
m->m_num_active_mds = n = ceph_decode_32(p);
/*
* the possible max rank, it maybe larger than the m_num_active_mds,
* for example if the mds_max == 2 in the cluster, when the MDS(0)
* was laggy and being replaced by a new MDS, we will temporarily
* receive a new mds map with n_num_mds == 1 and the active MDS(1),
* and the mds rank >= m_num_active_mds.
*/
m->possible_max_rank = max(m->m_num_active_mds, m->m_max_mds);
m->m_info = kcalloc(m->possible_max_rank, sizeof(*m->m_info), GFP_NOFS);
if (!m->m_info)
goto nomem;
/* pick out active nodes from mds_info (state > 0) */
for (i = 0; i < n; i++) {
u64 global_id;
u32 namelen;
s32 mds, inc, state;
u8 info_v;
void *info_end = NULL;
struct ceph_entity_addr addr;
u32 num_export_targets;
void *pexport_targets = NULL;
struct ceph_timespec laggy_since;
struct ceph_mds_info *info;
bool laggy;
ceph_decode_need(p, end, sizeof(u64) + 1, bad);
global_id = ceph_decode_64(p);
info_v= ceph_decode_8(p);
if (info_v >= 4) {
u32 info_len;
ceph_decode_need(p, end, 1 + sizeof(u32), bad);
*p += sizeof(u8); /* info_cv */
info_len = ceph_decode_32(p);
info_end = *p + info_len;
if (info_end > end)
goto bad;
}
ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad);
*p += sizeof(u64);
namelen = ceph_decode_32(p); /* skip mds name */
*p += namelen;
ceph_decode_32_safe(p, end, mds, bad);
ceph_decode_32_safe(p, end, inc, bad);
ceph_decode_32_safe(p, end, state, bad);
*p += sizeof(u64); /* state_seq */
if (info_v >= 8)
err = ceph_decode_entity_addrvec(p, end, msgr2, &addr);
else
err = ceph_decode_entity_addr(p, end, &addr);
if (err)
goto corrupt;
ceph_decode_copy_safe(p, end, &laggy_since, sizeof(laggy_since),
bad);
laggy = laggy_since.tv_sec != 0 || laggy_since.tv_nsec != 0;
*p += sizeof(u32);
ceph_decode_32_safe(p, end, namelen, bad);
*p += namelen;
if (info_v >= 2) {
ceph_decode_32_safe(p, end, num_export_targets, bad);
pexport_targets = *p;
*p += num_export_targets * sizeof(u32);
} else {
num_export_targets = 0;
}
if (info_end && *p != info_end) {
if (*p > info_end)
goto bad;
*p = info_end;
}
dout("mdsmap_decode %d/%d %lld mds%d.%d %s %s%s\n",
i+1, n, global_id, mds, inc,
ceph_pr_addr(&addr),
ceph_mds_state_name(state),
laggy ? "(laggy)" : "");
if (mds < 0 || mds >= m->possible_max_rank) {
pr_warn("mdsmap_decode got incorrect mds(%d)\n", mds);
continue;
}
if (state <= 0) {
dout("mdsmap_decode got incorrect state(%s)\n",
ceph_mds_state_name(state));
continue;
}
info = &m->m_info[mds];
info->global_id = global_id;
info->state = state;
info->addr = addr;
info->laggy = laggy;
info->num_export_targets = num_export_targets;
if (num_export_targets) {
info->export_targets = kcalloc(num_export_targets,
sizeof(u32), GFP_NOFS);
if (!info->export_targets)
goto nomem;
for (j = 0; j < num_export_targets; j++) {
target = ceph_decode_32(&pexport_targets);
info->export_targets[j] = target;
}
} else {
info->export_targets = NULL;
}
}
/* pg_pools */
ceph_decode_32_safe(p, end, n, bad);
m->m_num_data_pg_pools = n;
m->m_data_pg_pools = kcalloc(n, sizeof(u64), GFP_NOFS);
if (!m->m_data_pg_pools)
goto nomem;
ceph_decode_need(p, end, sizeof(u64)*(n+1), bad);
for (i = 0; i < n; i++)
m->m_data_pg_pools[i] = ceph_decode_64(p);
m->m_cas_pg_pool = ceph_decode_64(p);
m->m_enabled = m->m_epoch > 1;
mdsmap_ev = 1;
if (mdsmap_v >= 2) {
ceph_decode_16_safe(p, end, mdsmap_ev, bad_ext);
}
if (mdsmap_ev >= 3) {
if (__decode_and_drop_compat_set(p, end) < 0)
goto bad_ext;
}
/* metadata_pool */
if (mdsmap_ev < 5) {
__decode_and_drop_type(p, end, u32, bad_ext);
} else {
__decode_and_drop_type(p, end, u64, bad_ext);
}
/* created + modified + tableserver */
__decode_and_drop_type(p, end, struct ceph_timespec, bad_ext);
__decode_and_drop_type(p, end, struct ceph_timespec, bad_ext);
__decode_and_drop_type(p, end, u32, bad_ext);
/* in */
{
int num_laggy = 0;
ceph_decode_32_safe(p, end, n, bad_ext);
ceph_decode_need(p, end, sizeof(u32) * n, bad_ext);
for (i = 0; i < n; i++) {
s32 mds = ceph_decode_32(p);
if (mds >= 0 && mds < m->possible_max_rank) {
if (m->m_info[mds].laggy)
num_laggy++;
}
}
m->m_num_laggy = num_laggy;
if (n > m->possible_max_rank) {
void *new_m_info = krealloc(m->m_info,
n * sizeof(*m->m_info),
GFP_NOFS | __GFP_ZERO);
if (!new_m_info)
goto nomem;
m->m_info = new_m_info;
}
m->possible_max_rank = n;
}
/* inc */
__decode_and_drop_map(p, end, u32, u32, bad_ext);
/* up */
__decode_and_drop_map(p, end, u32, u64, bad_ext);
/* failed */
__decode_and_drop_set(p, end, u32, bad_ext);
/* stopped */
__decode_and_drop_set(p, end, u32, bad_ext);
if (mdsmap_ev >= 4) {
/* last_failure_osd_epoch */
__decode_and_drop_type(p, end, u32, bad_ext);
}
if (mdsmap_ev >= 6) {
/* ever_allowed_snaps */
__decode_and_drop_type(p, end, u8, bad_ext);
/* explicitly_allowed_snaps */
__decode_and_drop_type(p, end, u8, bad_ext);
}
if (mdsmap_ev >= 7) {
/* inline_data_enabled */
__decode_and_drop_type(p, end, u8, bad_ext);
}
if (mdsmap_ev >= 8) {
/* enabled */
ceph_decode_8_safe(p, end, m->m_enabled, bad_ext);
/* fs_name */
ceph_decode_skip_string(p, end, bad_ext);
}
/* damaged */
if (mdsmap_ev >= 9) {
size_t need;
ceph_decode_32_safe(p, end, n, bad_ext);
need = sizeof(u32) * n;
ceph_decode_need(p, end, need, bad_ext);
*p += need;
m->m_damaged = n > 0;
} else {
m->m_damaged = false;
}
if (mdsmap_ev >= 17) {
/* balancer */
ceph_decode_skip_string(p, end, bad_ext);
/* standby_count_wanted */
ceph_decode_skip_32(p, end, bad_ext);
/* old_max_mds */
ceph_decode_skip_32(p, end, bad_ext);
/* min_compat_client */
ceph_decode_skip_8(p, end, bad_ext);
/* required_client_features */
ceph_decode_skip_set(p, end, 64, bad_ext);
ceph_decode_64_safe(p, end, m->m_max_xattr_size, bad_ext);
} else {
/* This forces the usage of the (sync) SETXATTR Op */
m->m_max_xattr_size = 0;
}
bad_ext:
dout("mdsmap_decode m_enabled: %d, m_damaged: %d, m_num_laggy: %d\n",
!!m->m_enabled, !!m->m_damaged, m->m_num_laggy);
*p = end;
dout("mdsmap_decode success epoch %u\n", m->m_epoch);
return m;
nomem:
err = -ENOMEM;
goto out_err;
corrupt:
pr_err("corrupt mdsmap\n");
print_hex_dump(KERN_DEBUG, "mdsmap: ",
DUMP_PREFIX_OFFSET, 16, 1,
start, end - start, true);
out_err:
ceph_mdsmap_destroy(m);
return ERR_PTR(err);
bad:
err = -EINVAL;
goto corrupt;
}
void ceph_mdsmap_destroy(struct ceph_mdsmap *m)
{
int i;
if (m->m_info) {
for (i = 0; i < m->possible_max_rank; i++)
kfree(m->m_info[i].export_targets);
kfree(m->m_info);
}
kfree(m->m_data_pg_pools);
kfree(m);
}
bool ceph_mdsmap_is_cluster_available(struct ceph_mdsmap *m)
{
int i, nr_active = 0;
if (!m->m_enabled)
return false;
if (m->m_damaged)
return false;
if (m->m_num_laggy == m->m_num_active_mds)
return false;
for (i = 0; i < m->possible_max_rank; i++) {
if (m->m_info[i].state == CEPH_MDS_STATE_ACTIVE)
nr_active++;
}
return nr_active > 0;
}
Reference in New Issue View Git Blame Copy Permalink